Net Loss Per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares shares in Thousands |
3 Months Ended | |
|---|---|---|
Apr. 30, 2019 |
Apr. 30, 2018 |
|
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
| Total potentially dilutive shares | 14,095 | 84,273 |
| Total all series | ||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
| Total potentially dilutive shares | 0 | 68,480 |
| Convertible preferred stock warrant | ||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
| Total potentially dilutive shares | 0 | 137 |
| Shares subject to outstanding common stock awards | ||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
| Total potentially dilutive shares | 14,053 | 15,656 |
| Shares issuable pursuant to the 2018 Employee Stock Purchase Plan | ||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
| Total potentially dilutive shares | 42 | 0 |